Means for assembling bowed retaining rings on shafts and the like



Aug. 15, 1961 H. ERDMANN 2,995,811

MEANS FOR ASSEMBLING BOWED RETAINING RINGS ON SHAFTS AND THE LIKE Filed July 8, 1958' 5 Sheets-Sheet 1 INVENTOR. HANS ERDMANN AT TOR NE Y Au 15, 1961 H. ERDMANN MEANS FOR ASSEMBLING BOWED RETAINING RINGS ON SHAFTS AND THE LIKE Fileu July s, 1958 5 Sheets-Sheet 2 Ir] I Hulk FIG. 3

' INVENTOR. I s HANS ERDMANN ATTORNEY Aug. 15, 1961 HIERDMANN MEANS FOR ASSEMBLING BOWED RETAINING RINGS ON SHAFTS AND THE LIKE Eileu July 8, 1958 5 Sheets-Sheet 3 INVENTOR. H A N S E R D M AN N ATTORNEY.

United States Patent 2,995,811 MEANS FOR ASSEMBLING BOWED RETAINING RINGS ON SHAFTS AND THE LIKE Hans Erdmann, Maplewood, NJ., assignor to Waldes Kohinoor, Inc., Long Island City, N.Y., a corporation of New York Filed July 8, 1958, Ser. No. 747,265 6 Claims. (Cl. 29211) This invention relates to improvements in means for assembling bowed retaining rings on shafts and the like, and more particularly to a combination retaining ring dispensing and applying tool for assembling bowed retaining rings generally, but more especially for assembling bowed rings having locking prongs as disclosed and claimed in Wurzel Patent No. 2,755,698, dated July 24, 1956, which with the present application is commonly owned.

As is now generally acknowledged, pronged bowed rings, -i.e. a form of open retaining ring which is bowed about its vertical center line and is provided with locking prongs which project from its convex face at' the approximate junctions between the ends of its arcuate inner edge and the inner ends of its gap edges, are not capable of being dispensed by means of the conventional retaining ring dispenser because the prongs of each lower ring of a stack thereof projects upwardly into the opening of the next higher ring, and thus withdrawal of said lower ring was impeded by engagement of its prongs with the ring above it. This difliculty was solved by the ring dispenser disclosed in my application Serial No. 666,397, filed June 18, 1957, now Patent No. 2,900,107, dated August 18, 1959, according to which a separate applicator tool, in addition to gripping the bowed middle portion of the lowermost one of a vertical stack of the pronged bowed rings arranged with their gaps facing to the rear or 'away from the tool, also pushed the next higher ring of the stack up an inclined surface, with the result that all rings above the ring being gripped were lifted an amount giving adequate clearance for the prongs of the gripped ring, whereby the latter could be simply withdrawn by the applicator tool, as with the plane retaining ring.

As distinguished from my aforesaid bowed ring dispenser requiring a separate hand-type applicator tool for its operation and whose operation further necessitates the lifting of all rings above the lowermost ring of the stack thereof during the course of each dispensing operation, the present invention contemplates and provides a combination dispensing and applying tool for assembling bowed retaining rings, and particularly such rings of the pronged type as disclosed in the aforesaid Wurzel Patent No. 2,755,698, in fully mechanized manner and without any requirement for lifting the ring or rings disposed above the lowermost ring being dispensed in the performance of each dispensing operation as was heretofore considered necessary.

As explained in the Wurzel patent aforesaid, bowed retaining rings provided with locking prongs have in their unstressed state greater overall axial dimension than the width of the shaft groove in which they are to be assembled, and accordingly such rings must be flattened, both in the ring body and in the prong portions thereof, prior to being assembled in their groove, to facilitate their relatively free entry into the groove and thereafter to achieve the spring locking effect of such rings. Accordingly, another main object of my present invention is the provision of a mechanized dispensing and applying tool for assembling pronged bowed rings as aforesaid, which incorporates simple yet eflective means for flattening the bowed ring. body and/ or its locking prongs of each ring being dispensed during the course of its travel from the 2 ring stack to the groove in which it is to be finally assembled, in fully automatic manner.

A more particular object of the invention is the provision of a practical and thoroughly dependable tool for the mass assembly of bowed retaining rings, especially of the type provided with locking prongs, in fully mechanized manner, and which combines power means for positively pushing the lowermost ring of a stack of! such rings disposed with their openings or gaps facing the shaft or other workpiece on which ring assembly is to be effected into the groove of said shaft, and means for automatically flattening each said ring during the course of its travel from the ring stack to groove, as facilitates entry of said ring into its groove.

The above and other objects and features of advantage of a bowed ring dispensing and applyingtool means according to the present invention will appear from the detailed description thereof, in which reference is had to the accompanying drawings illustrative of a preferred form of such means, in which:

FIG. 1 is a side elevation, partly in section, of said bowed ring dispensing and applying means as herein proposed;

FIG. 2 and FIG. 4 are enlarged scale, longitudinal sections of the working portion of the bowed ring dispensing and applying means according to FIG. 1, which illustrate the lowermost ring of the ring column in'its respective positions before and after assembly;

FIG. 3 is a plan view of FIG. 2, partly in section;

FIG. 5 is a perspective View, on an enlarged scale, of the bowed open retaining ring having locking prongs, for the assembly of which the present dispensing and applying means was especially designed;

FIG. 6 is an enlarged exploded View of the parts making up the slideway through which the lowermost ring of the stack thereof moves during the course of each dispensing operation, and which is provided with ring flattening means for eifecting flattening of the ring prior to its movement into the shaft groove in which it is to be assembled;

FIG. 7 is a perspective view of the slideway cover member and its ring flattening means as seen from below; and

FIG. 8 is a transverse section taken through the ring slideway on line 88 of FIG. 1, which illustrates the action of the flattening ribs on both the ring body and locking prongs of a pronged bowed ring moving through said slideway.

Referring to the drawings, FIG. 5 is illustrative of a pronged bowed ring of the general type disclosed and claimed in the aforesaid Wurzel Patent No. 2,755,698, for the assembly of which the present combination ring dispensing and applying means was especially devised. More particularly, such a ring designated R comprises an arcuate ring body 10 having a wide gap 11 between its open ends 12, 13 as characterizes the open retaining ring, and being bowed about its vertical center line so that it has concavo-convex shape, and being moreover provided with locking prongs 14, 15 which project from the convex face of the ring at approximately the junctions of the ends of its arcuate inner edge with the inner straight edges of the ring ends which define the aforesaid ring gap 11. The ring R is also shown to be provided with horizontally aligned notches or recesses 16, 17 disposed intermediate the prongs 14, 15, and the arcuate inner edge of the ring for the accommodation of the edges of a stack rod whereby said stack rod is enabled to accurately align the rings placed thereon and to'guide them in their feed movement therealong. Illustratively, the ring R is also provided onopposite sides of its outer periphery with co-planar side Wings 18, 19 which serve to stabilize the ring when it rests on a flat surface with 3 its convex face upwardly disposed. As explained in the aforesaid Wurzel Patent No. 2,755,698, the overall axial dimension of such a bowed ring having locking prongs is greater than the width of the shaft groove in which it is to be assembled, whereby the fully seated ring will exert spring pressure on the machine part for which it forms a locating shoulder and its locking prongs will perform their locking function, and accordingly, to freely assemble same, the ring must be flattened prior to its entry into the groove. Referring now to FIG. 1 and FIGS 68, the herein proposed combination dispensing and applying means for assembling such pronged bowed rings illustratively comprise abase 20 mounting at one end thereof an air cylinder 21, at its intermediate portion an upright frame member 22, and at its other end a support block 23 for temporarily securing in place a holding fixture for a shaft S, in the groove g of which a ring R is to be assembled. By reference to FIGS. 2 and 4 in particular, it will be noted that the shaft is held in vertical position, that the upper end face of the fixture 24 is accurately aligned with one (the lower) side wall of the shaft groove, and also that said groove, being disposed above said end-face, is fully accessible to the reception of the ring to be assembled therein. Also to be understood is that the so-called fixture 24 may in fact constitute the machine part such as a gear, bearing race, bushing or the like for which the assembled ring is to provide an artificial locating shoulder serving to secure and locate said machine part on the shaft S. V i The aforesaid base-mounted frame 22 has an angled flange 27 formed integral with or aflixed to its forward vertical edge, which latter is preferably offset from the frame proper as shown, and aifixed to said flange is a vertical post 28 whose upper edge is provided with the usual hooks for securing the upper removable part (not shown) of the stack rod thereto, and to which the lower fixed part of the stack rod 29'is aflixed as by riveting, it being observed that the stack rod depends a substantial distance downwardly from the angled flange 27 of said frame. The lower end of the stack rod 29 is free of the frame and may or may not be flexible, and thus the stack rod device as a whole is adapted to mount a plurality of the rings R to be assembled, positioned thereon with their gaps facing or opening towards the shaft S held for ring assembly therewith, in aligned stack formation. The stack or column of rings held by the stack rod 29 rests on a support 31 preferably having (FIG.- 6) an upwardly convex surface complemental to the concave under-surface of the body portion of the rings R. Thus, a bowed retaining ring resting on the support 31 is supported throughout substantially its arcuate length by a complemental supporting surface. Said ring stack support 31 in turn rests on the upper horizontal face of a support plate 32a, which may be integral with or formed separately from the forward end of the horizontal bottom wall 32 of an elongated, longitudinally bored housing 34 secured as by means of an angled flange 22a to the aforesaid upright frame member 22. Said housing 34 extends from the aforesaid ring stack support 31 rearwardly towards the air cylinder 21, and reciprocable in thetbore thereof is a plunger 35 secured at its rearward end by means of a coupling 36 to the piston rod 37 of a piston 38 reciprocable in the aforesaid air cylinder 21. Illustratively, the air cylinder 21 is of the single-acting type, the piston 38 being positively actuated throughout its working stroke (to the left) against the force of a spring by compressed air supplied through the inlet 39, the energy stored in the spring being utilized to effect return movement of the piston. Inasmuch as the valve means for controlling admission and cut-off of compressed air is conventoinal, no attempt has been made to illustrate same.

As best seen in FIGS. 2 and 6, the forward end 35a of the plunger 35 operating within the bore of the aforesaid housing 34 has reduced section, and said reducedsection end is adapted to be projected through a longitudinal, open-top slot or groove 41 extending centrally through the aforesaid ring-stack support 31. By design, the vertical dimension of the reduced plunger end 35a is such that its upper edge extends above the topmost or apex line of the ring-stack support 31 a distance corresponding to the thickness of a single ring supported thereon. Accordingly, with each power stroke of the plunger 35, the lowermost ring of a stack thereof is pushed from the ring support 31 in leftwise direction towards the shaft S on which ring assembly is to be effected, and hence is dispensed from the stackof rings resting on said support. It will be understood that, to make this possible without interference from the stack rod 29, whose lower end would otherwise hold against the middle portion of the ring being pushed laterally from the ring support 31 as aforesaid, the stack rod terminates short of the support '31 a distance corresponding substantially to the axial thickness of a single ring, and thus the lowermost ring of the ring stack is always free to move laterally from the ring stack when so pushed by the plunger 35a. Also to be noted is that, since the rings are always disposed so that their gaps open in the direction in which the lowermost ring is pushed from the support 31 as aforesaid, the upwardly projecting prongs 14, 15 of said lowermost ring will move through the gap of the next higher ring without engaging or locking therewith, and thus there is no requirement to lift the next and all higher rings from the ring being dispensed the amount necessary to free the prongs of the latter ring from the next higher ring, as was present in the ring dispenser of the type disclosed in my aforesaid Patent No. 2,900,107, wherein the rings are stacked with their closed middle portions facing the shaft on which assembly is to be effected.

According to a further feature thereof, the invention provides means for flattening said lowermost ring R pushed from the ring-stack support 31 by an amount such that the flattened ring has axial dimension slightly less than the width of the shaft groove g, responsively to its movement from said support to said groove. As best seen in FIG. 6,. such means includes a forward extension 44 on the housing 34 whose free end has fork-like construction as defined by arms 45,46 spaced by a cut-out 47 extending rearwardly to the ring-stack support 31 and whose rearward closed or blind end in fact provides an access opening to said ring-stack support. By reference to FIG. 8, the spaced arms 45, 46 of the extension member 44 form the sides of a ring slideway for the ring being pushed by the plunger end 35a as aforesaid. The bottom wall of such slideway is formed in part by the aforesaid support plate 32a, and the slideway is closed on top by a top member 48 having general plate-like construction, as shown in FIGS. 6 and 8. Referring particularly to FIG. 7, said top member is provided on its under face with a pair of longitudinally extending, relatively widely spaced ribs 50, 51 which, by reference to FIG. 7, have progres sively increasing depth as they extend from the rearward or stack-rod end of the plate member towards its other or front end. As will be understood from FIGS. 5 and 8, the slideway top member 48 is secured flush against the arms 45, 46 of the housing extension member 44, whereby its under-face ribs 50, 51 depend into the cut-out 47 of said extension member. In addition to the aforesaid ribs 50, 51, the slideway top member 48 is provided on its under face with a pair of generally similar ribs 52, 53, also have progressively increasing depth, but it will be observed that said ribs 52, 5-3 are spaced apart a lesser distance and also have lesser depth than the aforesaid ribs 50, 51.

The action of said ribs 50, 51 and 52, 53 in flattening each ring moving from the ring-stack support 31 to the shaft groove in which it is to be assembled is briefly as follows: As seen in FIGS. 6 and 8, the lateral spacing of the ribs 50, 51 is such that their under surfaces are adapted to overlie and press down on the side-arm portions of each ring R moving along the slideway, i.e. the portions of the ring body extending symmetrically to the sides of a vertical ring center-line extending through its middle portion and gap. Consequent to the progressively increasing depth thereof, said ribs 50, 51 effect a consttiction in the depth of the ring slideway portions defined by their under surfaces and the horizontal top surfaces of the aforesaid plate member 32a on..which the ring-stack support 31 rests and the fixture 24, which latter extends in continuation of the aforesaid-plate-member top surface as is indicated in FIGS. 1, 2 and 4. Thus, as the ring moves along the slideway, it is progressively flattened to an axial dimension corresponding substantially to the width of the shaft groove g and hence its entry into the shaft groove when pushed thereinto by the plunger end 35a is greatly facilitated. Since the ring prongs 14, 15 must also be flattened to some extent, the aforesaid ribs 52, 53 are provided for this purpose, it being understood that the latter ribs are positioned to overlie and press down on the prongs of the ring being pushed through the slideway, thus to progressively flatten same by an amount enabling the prongs to move relatively freely through the gap of the shaft groove as the ring is forcibly projected thereinto.

Since the slideway top-plate 48 must extend fully to and fork the shaft on which ring assembly is to be effected, it is provided in its forward end with a shaft cutout 55; and it will also be understood that since it is desirable that the slideway receive the lowermost ring of the stack immediately upon said ring being pushed from the ring-stack support 31, said slideway top-plate 48 extends rearwardly to approximately the ring stack. Preferably, use is made of the rearward end of the top plate in maintaining accurate alignment of the lower rings of the stack thereof, as by mounting on or providing said rearward end with a block 56, the rearward face of which is formed with a rearwardly extending rib-like finger 57 of appreciable vertical dimension. By proper dimensioning and location of the finger 57, such is adapted to extend into the gaps 11 of a plurality of the lower rings R of the stack, thus to insure their accurate alignment.

Without further analysis, it will be seen that the above described and illustrated apparatus achieves in simple yet highly effective manner the objectives of the invention as explained above. More particularly, the invention provides a simple means for assembling bowed rings on their shafts without any requirement for lifting the ring immediately above the lowermost ring being dispensed from a stack of such rings, as was a requirement of the ring dispensing means disclosed in my aforesaid Patent No. 2,900,107, and thus the dispensing operation is greatly simplified. Moreover, by effecting automatic flattening of each ring in the course of its positive movement from the ring stack to the groove of the shaft in which it is to be assembled, the assembly operation is facilitated and speeded up, as compared to the prior assembly operation depending on manual ring flattening. Automatic ring flattening as herein proposed is of further advantage in that the amount of flattening required for a particular ring size or type of ring-assembly operation can be precisely controlled, which was not always possible in assembling bowed rings by the prior hand-operated applying tools.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. Means for assembling open retaining rings which are bowed about their vertical center line on grooved shafts and the like, the bowing of which results in the rings having greater overall axial dimension than the width of the grooves in which they are to be assembled, said means comprising, in combination, means for supporting a grooved shaft in temporarily fixed position in which its groove is accessible to the reception of a 'bowed retaining ring to be assembled therein, a ring-stack supporting member disposed in lateral alignment with the groove of a shaft supported as aforesaid and providing a rest for the lowermost ring of a stack of such bowed rings positioned with their concave sides facing downwardly, a stack rod operatively associated with and positioned above the supporting member for maintaining the plurality of rings in aligned stack arrangement and with their gaps opening towards the grooved shaft supported as aforesaid, the lower end of the stack rod terminating short of said ringsupporting member a distance corresponding to the axial dimension of the middle portion of one of said rings to be assembled whereby the lowermost ring of the stack thereof resting on said supporting member may be displaced laterally from the stack without interference from the stack rod, means operatively associated with said stack rod for positively pushing said lowermost ring in lateral direction from the stack and thence into the groove of the shaft supported as aforesaid, and means operatively interposed between the ring-stack supporting means and the shaft supporting means for progressively flattening said lowermost ring to an overall axial thickness corresponding substantially to the width of the groove responsively to its movement to the shaft groove as aforesaid.

2. Means for assembling bowed open retaining rings substantially as set forth in claim 1, wherein said last means comprises means forming a ring slideway extending between said ring-stack supporting and shaft supporting means and including means for effecting a progressive decrease in the depth of the slideway to that corresponding to the width of the groove.

3. Means for assembling bowed open retaining rings substantially as set forth in claim 1, wherein said last means comprises upper and lower slideway-forming members defining a slideway extending between said ring-stack supporting and shaft supporting means, the upper slideway member having on its under face a pair of longitu dinal ribs depending into the slideway passage and engaging on the upper face of a ring moving therealong, said ribs having progressively increasing depth whereby to effect a progressive flattening of said ring.

4. Means for assembling bowed open retaining rings substantially as set forth in claim 1, wherein said last means comprises lower and upper slideway-forming members defining a ring slideway extending between said ringstack supporting and shaft supporting means, the entrance end of said slideway having depth corresponding substantially to the overall axial dimension of said ring in its unstressed state, and the exit end of the slideway having depth corresponding substantially to the width of the groove of the shaft supported as aforesaid and the slideway having progressively decreasing depth between its said entrance and exit ends.

5. Means for assembling bowed open retaining rings substantially as set forth in claim 1, wherein said last means comprises upper and lower slideway-forming members defining a ring slideway extending between said ringstack supporting and shaft supporting means, said upper member having on its under face inner and outer pairs of longitudinally extending ribs of gradually increasing depth depending into said slideway and decreasing the depth thereof by an amount as to effect flattening of the ring to an axial dimension corresponding to the width of the groove in which it is to be assembled, said outer pair of ribs being spaced apart an amount such that they are adapted to bear on the side-arm portions of a ring moving along the slideway, and said inner pair of ribs being spaced apart an amount such that they are adapted to wherein the rings are so bowed about their vertical center 5 line that they have an overall axial dimension greater than the width of the grooves into which they are to be assembled, the improvement comprising means for supporting one of said rings in operative position laterally of a temporarily fixed groove shaft and generally in the 10 plane of the groove thereof, pushing means operatively associated with said supporting means for positively pushing said ring from said supporting means and thence along a fixed path leading to the groove of said shaft, and

means operably associated with said pushing means for flattening said ring to an overall axial thickness corresponding substantially to the width'of the groove responsively to its movement along said path to the shaft groove.

' References Cited in the file of this patent UNITED STATES PATENTS.

: 2,360,423 Johnson Oct. 17,1944

2,781,515 Juilfs Feb. 19, 1957 2,840,892 Erdmann- July 1, 1958 FOREIGN PATENTS 789,772 Great Britain Jan. 29, 1958 

